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Recent studies focusing on greenhouse gas emission reduction strategies indicate that material recycling has a significant impact on energy consumption and greenhouse gas emissions. The question arises how these effects can be quantified. Material recycling is not at all or insufficiently considered in energy system models, which are used today to derive climate gas mitigation strategies. To better assess and quantify the effects one option would be to couple energy system models and material flow models. The barriers and challenges of a successful coupling are addressed in this article. The greatest obstacles are diverging temporal horizons, the mismatching of system boundaries, data quality and availability, and the underrepresentation of industrial processes. A coupled model would enable access to more robust and significant results, a response to a greater variety of research questions and useful analyses. Further to this, collaborative models developed jointly by the energy system and material analysis communities are required for more cohesive and interdisciplinary assessments.

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Hydrocarbon fuels such as natural gas or biogas commonly contain small amounts of impurities like sulfur which result in a strong degradation of the polarization resistance (R pol) in Ni/YSZ anodes. The sulfur poisons the nickel catalyst and hinders the electrooxidation of hydrogen. At common SOFC operation temperatures above 700 °C the R pol of a Ni/GDC anode is less influenced. The trend to a significantly lower operating temperature of SOFCs even below 600 °C raises the question to which extend the sulfur tolerance of ceria-based anodes is maintained. We analyzed the impact of H2S on the R pol of four ceria-based anodes, differing in their microstructure, at an operation temperature of 600 °C by electrochemical impedance spectroscopy (EIS). The distribution of relaxation times (DRT) analysis is applied to deconvolute the electrochemical processes followed by a complex nonlinear least square approximation to quantify the loss processes and the impact of sulfur.